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Genistein, an isoflavonoid that can inhibit protein tyrosine kinase (PTK) phosphorylation, has been shown to play pivotal roles in the signal transduction pathways of hypoxic disorders. In this study, we established a rat model of isolated beating atrium and investigated the regulator role of genistein and its downstream signaling pathways in acute hypoxia-induced atrial natriuretic peptide (ANP) secretion. Radioimmunoassay was used to detect the ANP content in the atrial perfusates. Western blot analysis was used to determine the protein level of hypoxia-inducible factor 1[alpha] (HIF-1[alpha]), and GATA4 in the atrial tissue. The results showed that acute hypoxia substantially promoted ANP secretion, whereas this effect was partly attenuated by the PTKs inhibitor genistein (3 [micro]M). By Western blotting analysis, we found that hypoxia-induced increase in phosphorylation of Akt and transcriptional factors, including HIF-1[alpha], were also reversed by genistein. The perfused HIF-1[alpha] inhibitors rotenone (0.5 [micro]M) or CAY10585 (10 [micro]M) plus genistein significantly abolished the enhanced ANP section induced by hypoxia. Additionally, the perfused PI3K/Akt agonist insulin-like growth factor 1 (30 [micro]M) also abolished ANP secretion induced by genistein and inhibited expression of HIF-1[alpha]. In summary, our data suggested that acute hypoxia markedly increased ANP secretion by PTKs through the phosphoinositide-3 kinase (PI3K)/HIF-1[alpha] dependent pathway. Key words: atrial natriuretic peptide, hypoxia, hypoxia inducible factor-1a, protein tyrosine kinases, genistein. On a montre que la genisteine, un isoflavonoide pouvant entrainer une inhibition de la phosphorylation des PTK (<< protein tyrosine kinases >>), joue un role central dans les voies de transduction des signaux dans les troubles hypoxiques. Dans cette etude, nous avons mis au point un modele d'atrium contractile isole chez le rat, et etudie le role regulateur de la genisteine et ses voies de signalisation en aval dans la secretion de peptide natriuretique atrial (ANP) engendree par l'hypoxie aigue. A l'aide d'un radioimmunoessai, nous avons evalue les taux d'ANP dans les perfusats atriaux. A l'aide de l'immunobuvardage de Western, nous avons etabli les taux en proteines d'HIF-1[alpha] (<< hypoxia-inducible factor-1a >>) et de GATA4 dans le tissu atrial. Les resultats ont montre que l'hypoxie aigue favorise substantiellement la secretion d'ANP, tandis que cet effet s'attenuait partiellement avec l'inhibiteur des PTK genisteine (a 3 [micro]M). A l'aide de l'immunobuvardage de Western, nous avons observe que l'augmentation de la phosphorylation d'Akt et de facteurs de la transcription, y compris HIF-1[alpha], engendree par l'hypoxie etait aussi inversee avec la genisteine. La perfusion des inhibiteurs de l'HIF-1[alpha] rotenone (a 0,5 [micro]M) ou CAY10585 (a 10 [micro]M) avec la genisteine permettait clairement d'inhiber completement l'augmentation de la secretion d'ANP engendree par l'hypoxie. De plus, la perfusion de l'agoniste de l'axe PI3K/Akt IGF-1 (a 30 [micro]M) a aussi permis d'inhiber completement la secretion d'ANP engendree par la genisteine, ainsi que d'inhiber l'expression de l'HIF-1[alpha]. En resume, nos donnees laissaient entendre que l'hypoxie aigue entrainerait une augmentation marquee de la secretion d'ANP engendree par les PTK par l'intermediate de la voie de signalisation dependante de PI3K/HIF-1[alpha]. [Traduit par la Redaction] Mots-cles: peptide natriuretique atrial, hypoxie, HIF-1[alpha], PTK, genisteine., Introduction Atrial natriuretic peptide (ANP) is one of the cardiac hormones synthesized and primarily stored in the cardiac atria with multiple functions on cardio-related disease (Cannone et al. 2019; Zhou [...]

This study explores the low‐temperature pyrolysis kinetic of low metamorphic grade coal from Northern Shaanxi, utilizing Fourier transform infrared (FT‐IR) spectroscopy to analyze the characteristics of various functional groups over a 293–1023 K temperature range. A kinetic model, correlating with the pyrolysis behaviors of these groups, was developed through thermal analysis kinetics. Computational fluid dynamics (CFD) technology simulated the furnace's flow dynamics, allowing an examination of the physical field alterations and functional group evolution during pyrolysis. Results showed that the pyrolysis kinetic functions for aromatic C–H, C=C, C–O, and •OH, along with temperature, pressure, and velocity fields, were successfully integrated into the simulation. This integration provided detailed insights into the temperature profile, pressure distribution, flow velocities, and functional group distribution in the furnace. Aliphatics, exhibiting the largest mass fraction and wide pyrolysis temperature range, and •OH radicals with the highest activation energy were concentrated in the furnace's pyrolysis zone center. C=C's distribution was influenced by aromatic C–H and aliphatics, showing a complementary pattern. The oxygen‐containing groups C–O and C=O had similar pyrolysis mechanisms and uniform distribution. The functional groups' mass fractions were ranked from highest to lowest as follows: aliphatics > •OH > aromatic C–H > C–O > C=C > C=O. [ABSTRACT FROM AUTHOR]

Abstract Background Cigarette smoking has been shown to be one of the most important risk factors for cardiovascular diseases. However, little is known about cumulative effects of daily tar and nicotine intake on the risk of incident myocardial infarction (MI) so far. To bridge this gap, we conducted an analysis in a large prospective study from Southern Germany investigating associations of daily tar and nicotine intake with an incident MI event. Methods The study was based on 4,099 men and 4,197 women participating in two population-based MONICA Augsburg surveys between 1984 and 1990 and followed up within the KORA framework until 2002. During a mean follow-up of 13.3 years, a number of 307 men and 80 women developed an incident MI event. Relative risks were calculated as hazard ratios (HRs) estimated by Cox proportional hazards models adjusted for cardiovascular risk factors. Results In the present study, male regular smokers consumed on average more cigarettes per day than female regular smokers (20 versus 15) and had a higher tar and nicotine intake per day. In men, the MI risk compared to never-smokers increased with higher tar intake: HRs were 2.24 (95% CI 1.40-3.56) for 1-129 mg/day, 2.12 (95% CI 1.37-3.29) for 130-259 mg/day and 3.01 (95% CI 2.08-4.36) for ≥ 260 mg/day. In women, the corresponding associations were comparable but more pronounced for high tar intake (HR 4.67, 95% CI 1.76-12.40). Similar associations were observed for nicotine intake. Conclusions The present study based on a large population-based sample adds important evidence of cumulative effects of tar and nicotine intake on the risk of incident MI. Even low or medium tar and nicotine intake revealed substantial risk increases as compared to never-smokers. Therefore, reduction of tar and nicotine contents in cigarettes cannot be seen as a suitable public health policy in preventing myocardial infarction.

Abstract Background Chronic kidney disease (CKD) is becoming a major public health problem worldwide. This article reviews the published evidence of prevalence of CKD in population-based study samples that used the standardized definition from the Kidney Disease Outcomes Quality Initiative of the National Kidney Foundation (K/DOQI) practice guideline, and particularly focus on performance of serum-creatinine based equations for GFR estimation. We provide a summary of available data about the burden of CKD in various populations. Methods We performed a systematic review of available published data in MEDLINE. A combination of various keywords relevant to CKD was used in this research. Related data of included studies were extracted in a systematic way. Results A total of 26 studies were included in this review. The studies were conducted in different populations, and the number of study participants ranged from 237 to 65181. The median prevalence of CKD was 7.2% in persons aged 30 years or older. In persons aged 64 years or older prevalence of CKD varied from 23.4% to 35.8%. Importantly, the prevalence of CKD strongly depended on which estimating equations were used. The Modification of Diet in Renal Disease Study (MDRD) equation was likely to be preferred in recent epidemiological studies compared to the adjusted Cockcroft-Gault (CG) equation. Conclusion Worldwide, CKD is becoming a common disease in the general population. Accurately detecting CKD in special groups remains inadequate, particularly among elderly persons, females or other ethnic groups such as Asians.

Abstract Several microRNAs (miRNAs) expressed in the retina were confirmed to involve in retinal cell apoptosis, which was closely linked with the development of retinal diseases. Our previous studies have confirmed a vital role of miR-187 in retinal cells apoptosis. The aim of this study was to further elucidate the precise role of miR-187 and its probable mechanisms in RGC-5 cells apoptosis. The cellular oxidative stress status was assessed by reactive oxygen species (ROS) production and malondialdehyde (MDA) level. Our results showed that the elevated pressure, glutamate and H 2 O 2 -induced oxidative stress in RGC-5 cells was accompanied by a decrease in miR-187 expression and an increase in P2X7R expression. However, overexpression of miR-187 reversed this activation of oxidative stress in RGC-5 cells. Moreover, we also revealed that miR-187 inhibited the oxidative stress-induced apoptosis of RGC-5 cells through negative regulating P2X7R, probably through interacting with the 3′UTR of P2X7R. Finally, we confirmed that the forced miR-187 expression alleviated oxidative stress injury in retina tissues of rat models with chronic ocular hypertension. Our data demonstrated that miR-187/P2X7R signaling was involved in retinal cell apoptosis, at least in part, through activating oxidative stress. [ABSTRACT FROM AUTHOR]

Objective To determine the effectiveness of GRGM-13 on oxidative stress induced apoptosis of retinal ganglion cells (RGCs) and revealed its possible mechanism. Materials and methods: Caspase-3 activity, MDA level, and glutathione peroxidase level were detected by Caspase-3 assay kit, Lipid Peroxidation MDA Assay Kit, and Total Glutathione Peroxidase Assay Kit, respectively. Protein levels of Bax, Bcl-2, p-p38 and p38 were observed by Western Blot. Reactive oxygen species assay kit was used to determine intracellular ROS level. Apoptotic cells were measured by flow cytometry. Results GRGM-13 inhibited apoptosis of RGCs and ROS level in rat retinal tissue and RGC-5 cells, and the decrease degree strengthened with the increase of GRGM-13 concentration. In addition, ROS upregulated p-p38 expression, while GRGM-13 reversed this effect. We also found that p38 inhibitor SB202190 did not change L-glutamate (Glu) or H 2 O 2 -induced ROS level, while SB202190 inhibited apoptosis of RGC-5 cells. Finally, we observed that P2 × 7R agonist BzATP reversed the inhibition effect of GRGM-13 on RGC-5 cell apoptosis, ROS level and p-p38 expression, while si-P2 × 7R inhibited oxidative stress-induced phosphorylation of p38. Conclusion GRGM-13 could inhibit oxidative stress-induced RGCs apoptosis via inhibiting P2RX7/p38 MAPK pathway, which revealed the possible mechanism of GRGM-13 on stress-induced RGCs apoptosis and provided new Chinese medicine for the treatment of glaucoma. [ABSTRACT FROM AUTHOR]

This study aims to determine the safe and effective autologous blood drawing time for preoperative autologous blood donation (PABDs) by comparing the outcome of two different schedules of PABDs. A total of 144 patients who underwent elective surgery (radical resection of digestive tract tumor, lumbarspinesurgery and Intracranial tumor resection) were retrospectively reviewed. 88 patients had donated autologous blood 2 days before the operation (group 1); 56 patients had donated autologous blood more than 3 days before the operation (group 2). Hb and Hct before the operation and on postoperative days one and three, allogeneic blood transfusions, total bleeding, postoperative length of stay, and length of stay were measured and compared. Hb at postoperative day one was lower in group 2 than in group 1 ( P < 0.05). Furthermore, Hb in group 1 was higher at postoperative day one than at postoperative day three ( P < 0.05). Differences in postoperative Hct, allogeneic blood transfusions, total bleeding and postoperative length of stay between these two groups were not statistically significant ( P > 0.05)., The difference in the average number of postoperative hospitalization days between these two groups was not statistically significant ( P > 0.05). The 2 days of PABD did not lead to any adverse recovery effect. It would be helpful to conduct preoperative autologous blood transfusions. [ABSTRACT FROM AUTHOR]